Mike Curl and Tysen Young emerged from Lake Elmo dripping wet Saturday afternoon, from their toes to their long, white-haired wigs.
The duo were some of the dozens of people who participated in the Billings Polar Plunge, the annual fundraiser for Special Olympics.
The event raises tens of thousands of dollars each year.
For Curl, the fundraising is personal. His sister participates in Special Olympics events.
"Plus it's just a good cause," he said.
Curl and Young's team, the Stillwater Mermaid Mafia, raised more than $3,000 and were one of the best costume award winners on the 40-degree day.
"It could have been snowing instead," said a shivering Young.
Geese perched on ice farther out on the lake, as if watching the parade of warm-blooded mammals willingly dash in-and-out of the frigid water — and in the case of the Stillwater Mermaid Mafia, carrying plastic tridents and wearing shimmering purple tights.
Medical personnel were on hand, but the event appeared to go smoothly as teams dashed from the beach to the water to tents set up to help them dry off.
Special Olympics of Montana holds 12 different plunges throughout the state, from Sidney to Whitefish.
The organization holds athletic events for children and adults with disabilities throughout the state. About 2,000 athletes — as old as 86 and as young as 8 — from 65 Montana communities participate in year-round events ranging from alpine skiing, swimming and powerlifting.
The group also offers leadership and health programs. About 4,000 volunteers help organize competitions and programs, and the organization is funded by donations.